Cholecystoduodenal fistula due to pancreatic carcinoma: CT diagnosis.

Spontaneous biliary-enteric fistula is almost always due to cholelithiasis or peptic ulcer disease; rarely is malignancy responsible. A patient with carcinoma of the pancreas who presented with gastrointestinal hemorrhage and pneumobilia due to a malignant cholecystoduodenal fistula is reported.